Electrical door-actuating apparatus



May 11, 1954 w. A. BEVIS I ELECTRICAL DOOR-ACTUATING APPARATUS Filed Oct. 9, 1952 Patented May 11, 1954 ELECTRICAL DOOR-ACTUATING APPARATUS William Albert Bevis, Pinner, England, assignor to C. A. V. Limited, London, England Application October 9, 1952, Serial No. 313,970

Claims priority,application Great Britain October 15, 1951 1 Claim. 1

This invention relates to electrical apparatus for actuating vehicle or other doors, of the type comprising a reversible electric motor, electromagnetic switches for controlling the motor, switches operable by the door, and an electromagnetic relay controlled by manually-operable switches for controlling the electromagnets acting on the motor-controlling switches.

It is required to provide an apparatus of the type aforesaid which in the event of temporary failure of the electric power supply while the door is in its closed position, shall prevent the door from automatically moving to its open position when the power is restored, and the object of the present invention is to enable this requirement to be met in a simple and reliable manner.

An apparatus in accordance with the invention includes a relay having a pair of fixed contacts, a movable contact co-operating with the fixed contacts, a spring for movin the movable contact to the door-opening position, an electromagnet for moving the said contact to the door closing position, and a door-operable switch which in the door closing movement closes a circuit for maintaining the electromagnet of the relay in action while the door is closed and power is available for actuating the door.

In the accompanying drawings:

Figures 1 and 2 are diagrams illustrating two embodiments of the invention for actuating pubm 110 vehicle doors.

Referring to Figure l, the door-actuating motor comprises a rotary armature a and opposite ly-acting field windings b, c, the source of current being a battery d. The winding b is operative during a door-opening movement of the motor, and the winding 0 during a door-closing movement. ihe circuit through the winding 1) is controlled by a switch e which is movable to its closed position by an electromagnet the winding of which is indicated by f. The circuit through the winding 0 is likewise controlled by a switch g and an electromagnet having a wind.- ing it. The motor, and its associated field windings and switches are connected to the battery as shown in the diagram.

The electromagnet winding f is arranged in a circuit which includes a door-operable switch 2" which may be a two-way switch as shown, or it may be a one-way switch. ihe corresponding door-operable switch 7' in the circuit of the electromagnet winding h is a two-way switch.

The switch 2' is connected to the fixed contact piece 7c of a relay and the switch 7' is connected to the other fixed contact piece m of the relay.

The movable contact piece n is movable in one direction by a spring (not shown) and in the other direction by an electromagnet the winding of which is indicated by 0. When the door is open the contact piece it bears against the fixed contact piece It under the'action of the said spring, and when the door is closed the contact piece n bears against the contact piece 1n and is moved to and held in this position against the action of the spring by the associated electromagnet. The contact piece it of the relay is connected to the battery circuit in the manner shown.

lhe switch 7' is also connected as shown to one end of the electromagnet winding 0 through one or more normally-closed push-button switches 12, situated in the vehicle, this switch (or any one of them when two or more are provided) being actuated when it is required to open the door. Also the said end of the winding 0 can be con nected to the battery circuit through a normallyopen push button switch q, this switch being closed when it is required to close the door. The other end of the winding 0 is connected to the battery circuit as shown.

One of the fixed contacts of the switch 7' is connected to one end of the electromagnet winding 11. and the other to a point in a circuit which includes a resistance 1' and a warning lamp 8 or other signalling means, which circuit is connected to the opposite ends of the battery. When it is not required to provide a signalling means, the second fixed contact is connected to the battery circuit as indicated by the dotted line. The signalling means serves to announce that the door is open. When the door is closed the signalling means is short-circuited through the switch 1' and contacts m, n.

If desired a second lamp t may be included in ie system for illuminating the step of the vehicle, and is contained in a circuit controlled by the switch 2'. When it is required to include the lamp t in the system the switch 2' is a two-way switch. Otherwise this switch may be a one-way switch as already mentioned.

*5 bringing the motor into action. When the door reaches its open position it moves the switches i, i to their opposite positions. To re-close the door the push-button switch q is closed. This causes the relay electromagnet to move the relay contact piece n into contact with the contact piece m for bringing into action the electromagnet winding h and causing the switch g to be closed. When the door is closed the switches i, 51' are thereby returned to the positions shown'in the diagram, and the current continues to flow through the winding 0 of the relay.

If while the door is closed, an interruption occurs in the power circuit, as for example by the blowing of a fuse, the system will become dead, and the relay contact piece n will move underthe action of the associated spring into contact with the contact piece k. As already stated the purpose of the invention is to prevent undesired opening of the door as a consequenceof such movement of the contact piece n when the current-supply is restored. This requirement is met by the fact that on restoration of the current the electromagnet carrying the winding 0 is immediately re-energised, and the contact piece 71 is returned into contact with the contact piece m, thereby interrupting the circuit through the winding f or" the electromagnet of the switch e which controls the door-opening movement of the motor.

In a modification or the arrangement shown in Figure 1, the switch 7' is a single pole switch, and its sole function is to control the circuit containing the winding 77,. In this case an additional single pole switch movable to its closed position by the door when the latter is closed is connected tially similar to that shown in Figure l, and differs'only'inthat the motor is provided with a single field winding b, and the direction of current through this winding is reversible by the switches g, 6. Each switch comprises a movable contact piece situated between two fixed contact pieces. The movable contact piece is movable in one direction by a spring and in the other direcn0 tion by the associatedelectromagnet. The diagram shows the positions of the various parts of the system when the door is closed. On opening the push-button switch p or any one of the pushbutton switchesp, the current flowing through 0 is interrupted. The contact piece n of the associated switch then moves to its other position. Current now passes through the winding 1 causing the movable contact of the associated switch e to be moved, so enabling current to flow through the field winding 17 of the motor in the appropriate direction for opening the door. When the push-button switch q is closed for closing the door current flows through the electromagnet "winding h,- causing the movable contact of the associated switch to be moved for enabling current to flow through the field winding 1) in the opposite direction.

The above described modification of the switch for Figure'l is also applicable to the arrangement shown in Figure 2.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

An electrical door-actuating apparatus comprising in combination with the door to be actuated, a reversible electric motor for imparting opening and closing movements to said door, a source of electric current, electromagnetic switches for controlling the supply or electric current from said source to said motor, operating circuits for said electromagnetic switches, additional switches operable by said door and arranged in said circuits, an electromagnetic relay for co-operating with said additional switches to control the supply of current from said source to said circuits, and manually operabie switches for controlling said relay, the latter having a pair of fixed contacts, a spring-loaded movable contact which, when said door is open, bears under the action of its-spring loading against one of said fixed contacts, an electromagnet for moving said movable contact in opposition to its spring loading into a position in which it bears against the other of said fixed contacts, and thereby initiates closing movement of said door, and a circuit closable by closing movement of said door for maintaining said electromagnet in action when the door is, closed, and current from said source is available for actuating said motor.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,388,182 Bedding et al. Oct. 30, 1945 2,430,729 Negri Nov. 11, 1947 2,545,775 Hall Mar. 20, 1951 2,588,028 McNinch Mar. 4, 1952 2,607,586 Schlytern Aug. 19, 1952 

